Block Construction

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ThorCon is designed so that essentially everything can be manufactured on a shipyard-like assembly line. A good shipyard requires about 5 man-hours to cut, weld, coat, and erect a ton of hull steel. The yards achieve this remarkable productivity by block construction. Sub-assemblies are produced on a panel line, and combined into fully coated blocks with piping, wiring, HVAC (and scaffolding if required) pre-installed. In the last step, the blocks, weighing as much as 600 tons, are dropped into place in an immense building dock.

ThorCon uses exactly the same production process except the blocks are barged to the site and dropped into place. The essential difference between shipyards and most other assembly lines, such as aircraft manufacturing, is that shipyards build blocks on the assembly line, not the final product. The final product is put together elsewhere. Thinking in terms of blocks rather than final product is a key element in the ThorCon philosophy.

But ThorCon’s structure is far simpler and much more repetitive than a ship’s. The silo hall employs concrete-filled, steel plate, sandwich walls. This results in a strong, air-tight, ductile building. A 1 GWe ThorCon requires about 17,000 tons of steel for the nuclear island, all simple flat plate. A properly implemented panel line will be able to produce these blocks using less than 2 man-hours per ton of steel.

Similarly, all the other components will be manufactured on an assembly line and delivered to the site as fully outfitted and pre-tested blocks. Each power module will require a total of 31 blocks. Upon arrival at the site, the blocks will be dropped into place and the wall and roof blocks welded together using the automatic hull welding machines the yards have developed for this purpose. The demo at the top of this page shows the sequence. The wall cells will then be filled with concrete. Nil form work is required.

Block construction is not just about productivity. It’s about quality. The system automatically enforces very tight dimensional control. Extensive inspection at the sub-assembly and block level are an essential part of the shipyard system. Inspection at the block level is easy. Defects and faults are caught early and can be corrected far more easily than after erection. In most cases, they will have no impact on the overall project schedule.

But to make the system work we must have big blocks — blocks that are far larger than can be transported by truck or rail. ThorCon blocks can be up to 23 m wide and 40 m long. Such blocks can be barged well up most major rivers, including the St. Lawrence and into the Great Lakes.